Pellicle

ABSTRACT

The present invention makes it possible to provide a pellicle having, on the inside of the pellicle frame, a tacky layer which exhibits excellent performance for holding foreign matters such as dust or dirt suspended in space defined by the pellicle and the mask, and resistance against light of short wavelengths such as excimer beam. The pellicle comprises a pellicle frame, a pellicle film stretched on one side of said pellicle frame, and a tacky layer formed on the inside of said pellicle frame and containing a greasy fluorine-contained resin.

This application claims the benefit under 35 U.S.C. §371 of prior PCTInternational Application No. PCT/JP97/04176 which has an Internationalfiling date of Nov. 17, 1997 which designated the United States ofAmerica, the entire contents of which are hereby incorporated byreference.

TECHNICAL FIELD

The present invention relates to a pellicle and, more specifically, to apellicle having a tacky layer with resistance against light of shortwavelengths such as of excimer beam and having excellent dust-proofproperty.

BACKGROUND ART

In a step of photolithography, a circuit pattern is transferred, byexposure to light, onto a silicon wafer coated with a resist, by using aphotomask obtained by forming a circuit pattern on the surface of aglass plate by the vacuum evaporation of chromium or the like metal orby using a reticle (hereinafter referred to as "mask"). In this step,when light is irradiated in a state where foreign matter such as dust ordirt is adhered on the circuit pattern on the mask, the foreign matteris transferred onto the wafer resulting in the formation of a wafer ofdefective quality. When light is projected by a stepper, in particular,it is very likely that the chips formed on the wafer become alldefective. Thus, adhesion of foreign matter on the circuit pattern ofthe mask could turn into a serious problem. In order to solve thisproblem, a pellicle has been developed and various contrivances havebeen proposed.

In general, a pellicle is obtained by stretching a transparent filmcomposed of nitrocellulose or the like on one side of a pellicle framemade of aluminum. Onto the other side of the pellicle frame is stuck adouble-sided tape so that it can be mounted on a mask. This structureprevents the invasion of foreign matter from the outer side. Even incase foreign matter sticks on the film, it is transferred in anout-of-focus state upon irradiation with light, and a serious problemdoes not arise.

However, foreign matter such as dust or dirt that has once stuck to theinside of the pellicle may often fall after the pellicle is mounted.Furthermore, it often happens that the material of the surface of thepellicle frame partly collapses and falls due to vibration or the like.It is not easy to prevent the formation of dust inside the pellicle oncethe pellicle is mounted on the mask. In order to prevent the formationof dust from the inside of the film or the pellicle frame, therefore, ithas been attempted to form a dust-preventing film by applying a tackysubstance onto the inner surface of the pellicle frame (JapaneseLaid-Open Patent Publication No. 8062/1989), to form a tacky substancelayer on the inner surface of the pellicle film (Japanese Laid-OpenPatent Publication No. 120555/1989, and to apply an organic polymer orthe like onto the whole surfaces of the pellicle frame to make thesurfaces smooth (Japanese Laid-Open Patent Publications Nos. 301199/1994and 43892/1995).

Applying an organic polymer or the like onto the whole surfaces of thepellicle frame to make it smooth is advantageous from the standpoint ofpreventing the formation of dust from the pellicle frame but is noteffective against the dust suspended in the pellicle. On the other hand,forming a tacky layer on the inside of the pellicle frame or the film isadvantageous from the standpoint of preventing the formation of dustfrom the inside of the pellicle and holding the suspended dust so thatthe dust will not stick onto the mask.

However, finer masking circuit patterns have been formed year afteryear, and light having short wavelengths such as excimer beam has beenprojected. Light having short wavelengths has large energy. Therefore,an acrylic adhesive agent, rubber adhesive agent, or silicone adhesiveagent that has heretofore been used as a tacky material for forming atacky layer, is subject to be deteriorated, such as scorched, solidifiedor fluidized, and fails to exhibit a function for preventing theformation of dust or for holding the suspended matters to a sufficientdegree.

DISCLOSURE OF THE INVENTION

The present invention was accomplished in view of the above-mentionedpoints, and provides a pellicle which exhibits excellent holdingperformance for holding foreign matters such as dust or dirt, and has,inside of the pellicle frame, a tacky layer having resistance againstlight of short wavelengths such as excimer beam.

In order to solve the above-mentioned problems, the present inventorshave conducted keen study, have discovered the fact that a tacky layercontaining a greasy fluorine-contained resin formed on the inside of thepellicle frame exhibits excellent tackiness to the dust or dirt, andmakes it possible to obtain a pellicle having a tacky layer that is notdeteriorated even when it is irradiated with the excimer beam, and havethus accomplished the present invention.

That is, the present invention relates to a pellicle comprising apellicle frame, a pellicle film stretched on one side of said pellicleframe, and a tacky layer formed on the inside of said pellicle frame andcontaining a greasy fluorine-contained resin.

It has been known that the fluorine-contained resin, in general,exhibits excellent resistance against the heat and chemicals, exhibitsno adhesiveness with many materials, and has a low coefficient offriction. The present invention, on the other hand, is based on adiscovery that the greasy fluorine-contained resin exhibits tackinessexceptionally for the dust or dirt, use of the greasy fluorine-containedresin as a tacky layer on the inner surface of the pellicle makes itpossible to maintain tackiness for the dust or dirt, and the tacky forceis not deteriorated even upon the irradiation with light rays such asexcimer beam but continues to stably hold the dust.

In the present invention, it is desired that the tacky layer exhibitsholding performance which does not permit foreign matter held under acondition (1) described below to fly under at least the conditions:

(1) in which foreign matter having a particle diameter of 100 to 130 μmand a weight of 1 to 3 μg is permitted to fall on a horizontal tackylayer having a thickness of 3 μm from the height of 1 cm so as to beheld by the tacky layer; and

(2) wind pressure is applied for 10 seconds with an initial pressure of0.6 kg/cm² G from a straight distance of 1 cm from the foreign matter atan angle of 45 degrees from the upper side.

It is desired that the greasy fluorine-contained resin used in thepresent invention has a weight average molecular weight (Mw) of from1000 to 1500 and, particularly, from 1100 to 1300 from the standpoint ofmaintaining tacky property for the dust and dirt. It is further desiredthat the greasy fluorine-contained resin is the one containing fluorinein an amount of from 12 to 80% by weight, preferably, from 28 to 75% byweight, and most preferably, from 45 to 70% by weight from thestandpoint of resistance against light.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a pellicle of the present invention;

FIG. 2 is a sectional view of the pellicle of the present invention;

FIG. 3 is a diagram of testing the holding performance of a tacky layerof the pellicle of the present invention; and

FIG. 4 is a diagram illustrating a method of measuring the wind pressureproduced by an air gun used in testing the holding performance of thetacky layer.

BEST MODE FOR CARRYING OUT THE INVENTION

The invention will now be described in detail with reference to thedrawings.

Pellicle of the Invention

A pellicle 1 of the invention has a pellicle frame 2, a pellicle film 3,and a tacky layer 5 having a predetermined holding force.

The pellicle frame 2 used in the invention may be the one that isusually used as a pellicle frame. The pellicle frame 2 may be made of analuminum alloy, a stainless steel, polyethylene or aluminum treated withblack Alumite. The whole surface of the pellicle frame may be furthercoated with an amorphous fluorine-contained polymer or the like. Amongthem, aluminum treated with black Alumite can be preferably used.

The thin film used in the present invention as the pellicle film 3 maybe the one that is usually used as a pellicle film. For example, thethin film used as the pellicle film 3 may be composed of nitrocellulose,ethyl cellulose, cellulose acetate, cellulose propionate, pullulancompounds, amorphous fluorine-contained polymer or silicone-modifiedpolyvinyl alcohol. Among them, the amorphous fluorine-contained polymeris preferably used having a sufficient degree of resistance against theexcimer beam.

The thin film is stretched and secured by adhesion over one opening ofthe pellicle frame 2, i.e., over the side on which the ray of lightfalls, via an adhesive agent layer 4 to thereby form the pellicle film3.

The pellicle 1 of the present invention has a tacky layer 5 containing agreasy fluorine-contained resin. Upon containing the greasyfluorine-contained resin, the tacky layer 5 exhibits resistance againstlight of short wavelengths such as excimer beam. The tacky layer 5further exhibits performance for adsorbing and holding dust or dirt aswill be described below. The tacky layer 5 that is provided inside ofthe pellicle frame 2 exhibits excellent performance for holding foreignmatter such as dust or dirt suspended in space defined by the pellicle 1and the mask, and further exhibits resistance against light of shortwavelengths such as excimer beam.

That is, the tacky layer 5 provided in the pellicle 1 of the presentinvention exhibits holding performance which does not permit foreignmatter held under a condition (1) described below to fly under at leastthe conditions:

(1) in which foreign matter having a particle diameter of 100 to 130 μmand a weight of 1 to 3 μg is permitted to fall on a horizontal tackylayer having a thickness of 3 μm from the height of 1 cm so as to beheld by the tacky layer; and

(2) wind pressure is applied for 10 seconds with an initial pressure of0.6 kg/cm² G from a straight distance of 1 cm from the foreign matter atan angle of 45 degrees from the upper side (see FIG. 3).

In testing the holding performance, the wind pressure may be produced byusing an air gun 6 or the like, and may be applied by placing the tip ofa nozzle 62 at a straight distance of 1 cm from the foreign matter 7 atan angle of 45 degrees from the upper side with respect to thehorizontal direction. As for the wind pressure under the condition (2),use is made of the air gun 6 having the nozzle 62 of an inner diameterof, for example, 0.65 mm and the air is blown onto the upper dish of aprecision balance 8 from a distance of 1 cm just over the upper dish ofthe precision balance 8 with an initial pressure of 0.6 kg/cm² G (seeFIG. 4). This pressure acting on the precision balance 8 is nearlyequivalent to a weight of 1.3 g that would be displayed. Correctly, theinitial pressure of 0.6 kg/cm² G stands for the air pressure of 0.6kg/cm² G produced from the nozzle. In practice, however, the pressure ofa decompression device 61 may be set to be 0.6 kg/cm² G.

Here, the words "foreign matter" are supposed to be dust or dirt thatcreate a problem for the pellicle. In testing the holding performance,there may be used glass beads, polystyrene beads, etc. Furthermore, thewords "does not permit foreign matter to fly" stand for that the foreignmatter does not escape from the tacky layer. The foreign matter thatmigrates on the tacky layer does not mean it is flying.

The present invention has a feature in that the tacky layer 5 contains agreasy fluorine-contained resin. It is desired that the greasyfluorine-contained resin has the weight average molecular weight andcontains fluorine in an amount as described above.

It is generally desired that the greasy fluorine-contained resincomprises a recurring unit represented by the following formula (1),##STR1## wherein X is a halogen atom such as fluorine, chlorine, bromineor iodine, and R is a fluorine atom or a trifluoromethyl group.

Its concrete examples include tetrafluoroethaylene low polymer,hexafluoropropylene low polymer, tetrafluoroethylene/hexafluoropropylenelow copolymer and chlorotrifluoroethylene low polymer. Among them, a lowpolymer of chlorotrifluoroethylene (CTFE; weight average molecularweight of 1100 to 1300) is desired from the standpoint of maintainingtackiness to the dust or dirt and resistance against light.

The greasy fluorine-contained resin is excellent from the standpoint ofmaintaining tackiness and resistance against light, and can be usedalone as a matter of course. When used alone, however, the greasyfluorine-contained resin tends to drip due to its fluidity.

To prevent the dust or dirt from sticking onto the mask or the like,therefore, it is desired that the greasy fluorine-contained resin whichforms the tacky layer is used in the form of a composition together withother polymer which can suppresses the fluidity of the tacky layer. Theother polymer used for suppressing the fluidity will be a thermoplasticresin or a thermosetting resin having a molecular weight high enough forforming a film.

Examples of the thermoplastic resin include fluorine-contained resin,olefin resin, styrene resin, acrylic resin, chlorine-contained resin,polyamide, thermoplastic polyester, polycarbonate, polyphenylene oxide,polyimide, polyamideimide, polysulfone, thermoplastic polyurethane, or amixture of two or more kinds thereof.

On the other hand, examples of the thermosetting resin includephenol-formaldehyde resin, furane-formaldehyde resin,xylene-formaldehyde resin, ketone-formaldehyde resin, urea formaldehyderesin, melamine-formaldehyde resin, alkyd resin, unsaturated polyesterresin, epoxy resin, bismaleimide resin, triaryl cyanurate resin,thermosetting acrylic resin, silicone resin, urethane resin, or amixture of two or more kinds thereof.

In this embodiment, it is desired that the greasy fluorine-containedresin is contained in a tacky composition in an amount of from 90 to98.7% by weight and, particularly, from 95 to 98% by weight.

In the tacky layer of the above-mentioned composition, it is believedthat the high-molecular polymer exists as a film, mesh or cells underthe surface of the pellicle, and that this system holds the greasyfluorine-contained resin to prevent it from being fluidized.

It is desired that the high-molecular resin can be compatible with thegreasy fluorine-contained resin and exhibits excellent resistanceagainst light. From this point of view, it is desired to use afluorine-conzained resin having a molecular weight large enough forforming a film.

That is, according to a preferred embodiment of the present invention,the tacky layer is a composition comprising (A) a greasyfluorine-contained resin and (B) a fluorine-contained resin having amolecular weight (high molecular weight) capable of forming a film. Inthis case, it is desired that the tacky layer is a compositioncontaining (A) the greasy fluorine-contained resin and (B) thehigh-molecular fluorine-contained resin at a weight ratio (A):(B) offrom 11:1 to 80:1, particularly, from 20:1 to 65:1 and, mostparticularly, from 20:1 to 50:1, from the standpoint of maintainingtackiness to the dust, resistance against light, and preventing thetacky film from dripping.

It is desired that the high molecular fluorine-contained resin (B) isthe one containing fluorine in an amount of from 12 to 80% by weight,particularly, from 28 to 75% by weight and, most particularly, from 45to 70% by weight, from the standpoint of resistance against light. It isfurther desired that the high-molecular fluorine-contained resin (B) hasa molecular weight high enough for forming a film and, generally, has amolecular weight, in terms of a weight average molecular weight, of notsmaller than 1×10⁴ and, particularly, from 1×10⁵ to 1×10⁶.

It is further desired that the high-molecular fluorine-contained resin(B) prevents the tacky layer from dripping during the use, during thestorage or during the transit despite of an increase in the temperature,and, usually, has a softening point of not lower than 50° C.,particularly, not lower than 60° C. and, most particularly, not lowerthan 75° C. It is further desired that the high molecularfluorine-contained resin (B) is soluble in a solvent which is commonlyused for the greasy fluorine-contained resin (A) at the time of beingapplied to the pellicle.

From the standpoint of film-forming property and adhesiveness to thepellicle frame, it is desired that the high-molecular fluorine-containedresin (B) is at least the one selected from the group consisting of aperfluorobutenylvinyl ether polymer, a copolymer of atetrafluoroethylene and a perfluoro(2,2-dimethyl-1,3-dioxole), acopolymer of a tetrafluoroethylene, a hexafluoropropylene and avinylidene fluoride, a copolymer of a hexafluoropropylene and avinylidene fluoride, and a copolymer of a chlorotrifluoroethylene and avinylidene fluoride. Among these fluorine-contained resins, a copolymer(THV) of tetrafluoroethylene, hexafluoropropylene and vinylidenefluoride, is particularly desired. These fluorine-contained resins maybe modified with a carboxyl group.

It is desired that the tacky layer used in the present inventionexhibits tackiness usually over a temperature range of from -10° C. to50° C. The tackiness can be confirmed by the above-mentioned testingmethod. This quite holds for the tackiness after irradiated with light.

According to the present invention, the tacky layer may be formed in athickness capable of holding dust or dirt, and there is no particularlimitation in the thickness thereof. Usually, however, it is desiredthat the thickness is from 1 μm to 1 mm, particularly, from 3 μm to 100μm and, most particularly, from 3 μm to 20 μm.

Preparation of Pellicle of the Invention

The pellicle 1 according to the present invention is prepared by formingthe tacky layer 5 on the inside of the pellicle frame 2, and stretchingthe pellicle film on one side of the pellicle frame 2 on which the rayof light falls.

To form the tacky layer 5, first, a coating solution is preparedcontaining a greasy fluorine-contained resin or further a polymer forsuppressing the fluidity. The coating solution is obtained by dissolvingthe greasy fluorine-contained resin or further the polymer forsuppressing the fluidity in a solvent capable of dissolving the greasyfluorine-contained resin.

The concentration of solid components in the coating solution variesdepending upon the composition of resins or the manner of coating, butis, usually, from 10 to 80% by weight and, particularly, from 30 to 70%by weight.

The coating solution is obtained by, for example, adding achlorotrifluoroethylene low polymer as a greasy fluorine-contained resinto a solvent of the type of ketone or ester such as ethyl acetate,isopropyl acetate or methyl ethyl ketone, followed by stirring. When thechlorotrifluoroethylene is used as the greasy fluorine-contained resin,furthermore, it is further desired to mix a fluorine-contained resin forsuppressing the fluidity. A copolymer of tetrafluoroethylene,hexafluoropropylene and vinylidene fluoride, or a copolymer ofhexafluoropropylene and vinylidene fluoride is added and is dissolvedthereby to obtain a coating solution. As required, furthermore, thecoating solution may be filtered under an elevated pressure.

The obtained coating solution can be applied to the inside of thepellicle frame by any known coating means, such as spray coating method,dipping coating method, brush coating method, knife coating method,roller coating method or spread coating method. In the case of thespread coating method, for example, liquid droplets placed on the frameare spread by using a jig so as to be uniformly applied thereon.Finally, the coating solution applied onto the frame is dried to form atacky layer.

After the tacky layer 5 is formed, a thin pellicle film is stretched onone side of the pellicle frame 2 on which the ray of light falls,thereby to obtain the pellicle 1 of the present invention. The thinpellicle film is stretched by a customary manner and is secured byforming an adhesive agent layer 4 using an adhesive agent that isusually used.

The adhesive agent will be the known one, such as cellulose derivative,chlorinated polypropylene, polyamide adhesive agent, fluorine-containedresin adhesive agent, acrylic adhesive agent, epoxy resin, or polyimideadhesive agent.

EXAMPLES

The present invention will now be described by way of the followingExamples to which only, however, the invention is in no way limited.

Example 1

A solution was prepared by dissolving a chlorotrifluoroethylene lowpolymer (trade name: Daifloyl #100 produced by Daikin Kogyo Co.,hereinafter simply referred to as CTFE) having a weight averagemolecular weight of 1100 to 1300 in ethyl acetate such that its amountwas 40% by weight.

A tetrafluoroethylene/hexafluoropropylene/vinylidene fluoride copolymer(Fluoroplastic THV 200 produced by Sumitomo 3M Co., hereinafter simplyreferred to as THV 200) was added to the above solution such that theweight ratio of CTFE:THV 200 was 30:1, followed by sufficient degree ofstirring. The weight average molecular weight of this THV 200 resinmeasured by GPC was 1.7×10⁵. By using a filter (porous diameter of 1.0μm) of polytetrafluoroethylene (PTFE), the solution was filtered underan elevated pressure to obtain a coating solution.

The coating solution was dripped on the surface in the inside of thewashed pellicle frame 2, and the droplets on the frame was stretchedusing a jig to uniformly apply it thereon. The coating was dried uponbeing left to stand at room temperature for one hour to thereby form thetacky layer 5.

Testing the Holding Performance

Glass beads 7 having a diameter of 105 μm weighing 1.5 μg were permittedto fall on the tacky layer 5 of the pellicle frame 2 from a height of 1cm, so that about five to ten of them were held on the tacky layer 5. Byusing an air gun 6, the air was blown onto the glass beads 7 with apressure of 0.6 kg/cm² from a distance of 1 cm at an angle of 45 degreesfrom the upper side (FIG. 3). However, no glass bead 7 flew from thetacky layer 5.

Testing the Resistance against Light

The tacky layer 5 was irradiated with light from a KrF excimer laser(248 nm) in a total of 2000 J/cm² under a condition of 5 mJ/cm² ·p×100Hz in order to test the holding performance (FIG. 3) after irradiationin the same manner as the above-mentioned testing of holdingperformance. No glass bead flew from the tacky layer.

The state of the irradiated portion was observed through a microscope,but no change was recognized in the surface state of the tacky layer.

The obtained results were as shown in Table 1.

Examples 2 to 4 and Comparative Examples 1 to 3

Coating solutions were prepared by blending ethyl acetate with theDaifloyl and THV 200 at mixing ratios of CTFE:THV 200 of 100:0, 100:1,60:1, 40:1, 20:1 and 10:1. These coating solutions were applied to thepellicle frames 2 to form tacky layers 5 having holding performances asshown in Table 1.

Glass beads 7 having a diameter of 105 μm weighing 1.5 μg were allowedto fall on the tacky layers 5 of the pellicle frames 2 from a height of1 cm, so that five to ten of them were held on the tacky layers. Byusing the air gun 6, the air was blown onto the glass beads 7 with apressure of 0.6 kg/cm² from a distance of 1 cm at an angle of 45 degreesfrom the upper side (FIG. 3) to examine the motion of the glass beads 7.

Furthermore, the pellicle frames 2 forming the tacky layers 5 were soheld that the surfaces of the tacky layers were at right angles with thehorizontal plane, left to stand at a temperature of 50° C. for 24 hours,and the surfaces of the tacky layers 5 were observed to make sure if thesurfaces were dripping or not.

The results were as shown in Table 1.

                  TABLE 1                                                         ______________________________________                                        Holding performance and preservability of the                                 tacky layers.                                                                                               Surface state at                                                 Motion of glass                                                                            50° C. after                             CTFE low polymer:                                                                              beads** (holding                                                                           24 hrs***                                       THV 200 resin    performance) (preservability)                                ______________________________________                                        Comp.  100:0 (0%*)   migrates and drips                                       Ex. 1                flies                                                    Comp.  100:1 (1.0%*) migrates and drips                                       Ex. 2                flies                                                    Ex. 2   60:1 (1.6%*) migrates     drips a little                              Ex. 3   40:1 (2.4%*) migrates     does not drip                               Ex. 4   20:1 (4.8%:) migrates     does not drip                               Comp.   10:1 (9.1%*) migrates and does not drip                               Ex. 3                flies                                                    ______________________________________                                         *Amount of THV 200 resin (% by weight) in the composition.                    **"Migrates and flies" means that the glass beads partly flew and partly      migrated on the tacky layer. "Migrates" means that the glass beads did no     fly from the tacky layer but migrated on the tacky layer.                     ***"Drips" means that the tacky layer dripped and the surface of the fram     was exposed. "Drips a little" means that the tacky layer dripped but the      surface of the frame was not exposed.                                    

The present invention makes it possible to provide a pellicle having, onthe inside of the pellicle frame, a tacky layer which exhibits excellentperformance for holding foreign matters such as dust or dirt suspendedin space defined by the pellicle and the mask, and resistance againstlight of short wavelengths such as excimer beam.

What is claimed is:
 1. A pellicle comprising:a pellicle frame, apellicle film stretched on one side of said pellicle frame, and a tackylayer formed on the inside of said pellicle frame and containing agreasy fluorine-contained resin wherein said greasy fluorine-containedresin has a weight average molecular weight of from 1000 to
 1500. 2. Apellicle according to claim 1, wherein said tacky layer exhibits holdingperformance which does not permit foreign matter held under a condition(1) described below to fly under at least the conditions:(1) in whichforeign matter having a particle diameter of 100 to 130 μm and a weightof 1 to 3 μg is permitted to fall on a horizontal tacky layer having athickness of 3 μm from the height of 1 cm so as to be held by the tackylayer; and (2) wind pressure is applied for 10 seconds with an initialpressure of 0.6 kg/cm² G from a straight distance of 1 cm from theforeign matter at an angle of 45 degrees from the upper side.
 3. Apellicle according to claim 1, wherein said greasy fluorine-containedresin is the one containing fluorine in an amount of from 12 to 80% byweight.
 4. A pellicle according to claim 3, wherein said greasyfluorine-contained resin comprises a recurring unit represented by thefollowing formula (1), ##STR2## wherein X is a halogen atom, and R is afluorine atom or a trifluoromethyl group.
 5. A pellicle according toclaim 1, wherein said greasy fluorine-contained resin is a low polymerof chlorotrifluoroethylene.
 6. A pellicle according to claim 1, whereinsaid tacky layer comprises a composition of a greasy fluorine-containedresin and a polymer for suppressing the fluidity, and said greasyfluorine-contained resin is contained in the composition in an amount offrom 90 to 98.7% by weight.
 7. A pellicle according to claim 1, whereinsaid tacky layer comprises a composition of (A) a greasyfluorine-contained resin, and (B) a fluorine-contained resin capable offorming a film.
 8. A pellicle according to claim 7, wherein saidadhesive layer comprises a composition containing (A) a greasyfluorine-contained resin and (B) a fluorine-contained resin capable offorming a film at a weight ratio (A):(B) of from 20:1 to 50:1.
 9. Apellicle according to claim 7, wherein the fluorine-contained resin (B)capable of forming a film contains fluorine in an amount of from 12 to80% by weight.
 10. A pellicle according to claim 7, wherein thefluorine-contained resin (B) capable of forming a film is at least theone selected from the group consisting of a perfluorobutenylvinyl etherpolymer, a copolymer of a tetrafluoroethylene and aperfluoro(2,2-dimethyl-1,3-dioxole), a copolymer of atetrafluoroethylene, a hexafluoropropylene and a vinylidene fluoride, acopolymer of a hexafluoropropylene and a vinylidene fluoride, and acopolymer of a chlorotrifluoroethylene and a vinylidene fluoride.
 11. Apellicle according to claim 7, wherein said adhesive layer comprises acomposition containing (A) a greasy fluorine-contained resin and (B) afluorine-contained resin capable of forming a film at a weight ratio of(A):(B) of from 11:1 to 80:1.
 12. A pellicle according to claim 7,wherein the fluorine-contained resin (B) capable of forming a filmcontains fluorine in an amount of from 28 to 75% by weight.
 13. Apellicle according to claim 7, wherein the fluorine-contained resin (B)has a molecular weight, in terms of weight average molecular weight, ofgreater than or equal to 1×10⁴.
 14. A pellicle according to claim 7,wherein the fluorine-contained resin (B) has a softening point ofgreater than or equal to 50° C.
 15. A pellicle according to claim 1,wherein said tacky layer is formed maintaining a thickness of from 3 to20 μm.
 16. A pellicle according to claim 1 wherein said greasyfluorine-contained resin has a weight average molecular weight of from1100 to
 1300. 17. A pellicle according to claim 1 wherein said greasyfluorine-contained resin is one containing fluorine in an amount of from28 to 75% by weight.
 18. A pellicle according to claim 1, wherein saidtacky layer comprises a composition of greasy fluorine-contained resinand a polymer for suppressing the fluidity, and said greasyfluorine-contained resin is contained in the composition in an amount offrom 95 to 98% by weight.
 19. A pellicle according to claim 1, whereinthe tacky layer exhibits tackiness over a temperature rage of from -10°to 50° C.